Abstract
We report Giant Metrewave Radio Telescope (GMRT), Very Large Telescope (VLT), and Spitzer Space Telescope observations of ESO 184−G82, the host galaxy of GRB 980425/SN 1998bw, that yield evidence of a companion dwarf galaxy at a projected distance of 13 kpc. The companion, hereafter GALJ193510-524947, is a gas-rich, star-forming galaxy with a star formation rate of 0.004 M yr−1, a gas mass of 107.1±0.1 M, and a stellar mass of 107.0±0.3 M. The interaction between ESO 184−G82 and GALJ193510-524947 is evident from the extended gaseous structure between the two galaxies in the GMRT H I 21 cm map. We find a ring of high column density H I gas, passing through the actively star-forming regions of ESO 184−G82 and the GRB location. This ring lends support to the picture in which ESO 184−G82 is interacting with GALJ193510-524947. The massive stars in GALJ193510-524947 have similar ages to those in star-forming regions in ESO 184−G82, also suggesting that the interaction may have triggered star formation in both galaxies. The gas and star formation properties of ESO 184−G82 favour a head-on collision with GALJ193510-524947 rather than a classical tidal interaction. We perform state-of-the-art simulations of dwarf-dwarf mergers and confirm that the observed properties of ESO 184−G82 can be reproduced by collision with a small companion galaxy. This is a very clear case of interaction in a gamma-ray burst host galaxy and of interaction-driven star formation giving rise to a gamma-ray burst in a dense environment.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 5411-5422 |
| Number of pages | 12 |
| Journal | Monthly Notices of the Royal Astronomical Society |
| Volume | 485 |
| Issue number | 4 |
| DOIs | |
| State | Published - Mar 13 2019 |
Funding
MA and SR would like to thank Bruce Elmegreen, Francoise Combes, Diane Cormier, and David Elbaz for valuable discussions. We thank the staff of the GMRT for making these observations possible. The GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. We acknowledge using data based on observations collected at the European Southern Observatory under ESO programmes 064.H-0375(A), 066.D-0576(A), and 165.H-0464(A). This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA, and also data made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. MA acknowledges support from UnivEarthS Labex programme at Sorbonne Paris Cité (ANR-10-LABX-0023 and ANR-11-IDEX-0005-02). SR acknowledges support from ERC Starting Grant no. 307209. LC is supported by DFF - 4090-00079. NK acknowledges support from the Department of Science and Technology via a Swarnajayanti Fellowship (DST/SJF/PSA-01/2012-13). The Flatiron Institute is supported by the Simons Foundation. The Cosmic Dawn Center is funded by the DNRF. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. MA and SR would like to thank Bruce Elmegreen, Francoise Combes, Diane Cormier, and David Elbaz for valuable discussions. We thank the staff of the GMRT for making these observations possible. The GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. We acknowledge using data based on observations collected at the European Southern Observatory under ESO programmes 064.H-0375(A), 066.D-0576(A), and 165.H-0464(A). This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA, and also data made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. MA acknowledges support from UnivEarthS Labex programme at Sorbonne Paris Cité (ANR-10-LABX-0023 and ANR-11-IDEX-0005-02). SR acknowledges support from ERC Starting Grant no. 307209. LC is supported by DFF – 4090-00079. NK acknowledges support from the Department of Science and Technology via a Swarnajayanti Fellowship (DST/SJF/PSA-01/2012-13). The Flat-iron Institute is supported by the Simons Foundation. The Cosmic Dawn Center is funded by the DNRF. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.
Keywords
- Galaxies: ISM
- Galaxies: interactions
- Galaxies: kinematics and dynamics
- Galaxies: star formation
- Gamma-ray burst: general
- Radio lines: galaxies
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science